when you tested it on another laptop, did you mean you were able to boot from it? or just view the contents? And what or how did you create the usb boot? UNetbootin? other?
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LogmanSep 1 '12 at 2:00

Change boot priority back to the hard drive (or whatever it was), save changes and exit bios then use F9 to get the one time boot menu, choose your usb drive from the list and hit enter.
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MoabSep 1 '12 at 2:03